So, I cleaned and tuned and replaced everything on my 1978 Puch Newport. I don't want to mess with the gear ratio until I have some more power. I don't think I'm ready to start porting just yet. What sort of modifications will increase HP? I am sorta new and have read about different carb sizes and jet sizes and heads etc. I have seen all sorts of advertisements 60 or 70 CC heads and big bore kits, but can someone explain what they do? I understand the basics of how the carb gets air/fuel into the cylinder and how that combusts to shove the piston, but beyond that I am a little fuzzy....
Make my 1 HP fly?
Re: Make my 1 HP fly?
ok: go to the wiki and learn a little more about cylinder kits
but the break down basically goes you are getting a larger displacement by switching to a bigger cylinder size. your stock newport is 49cc (cubic centimeters) if were to put this into car terms you have a .049L engine hehe since most cars run off of liters 5.0L(mustang)=5000ccs so in essence you are increasing the size of your engine. this boosts horse power output, and more power=more speed.
the bigger carb allows more fuel, and more air to come in, this equals to more action in the cylinder, and that means more speed again, the high compression heads increase the compression inside the cylinder itsself. and more compression again equals more power.
then you get into new exhaust systems. these can increase low mid and high end power depending on the pipe. some increase one, others are good at two. no pipes are equal across the board, or thats just stock..lol
jets are for tuning that added amount of fuel/air when you change to a new carb, or change filters, or run without one at all
Re: Make my 1 HP fly?
So lets say that I leave the stock alone and change to a 15mm carb. I currently have a 12mm carb (I think). With a de-restricted exhaust that would allow higher rpms and thus a higher top speed. Right?
Re: Make my 1 HP fly?
well....you wont notice toooooo much of a diffrence. one, if you JUST do the carb and not the intake, you won't go much faster. don't worry about de-restricting an exhaust, just buy a new one. for real, thats the first upgrade i'd go with, because you CAN make your 12mm carb into a 14 or 15, and the same goes with the intake.
Re: Make my 1 HP fly?
So really I'd need a bigger carb and a bigger kit then?
Re: Make my 1 HP fly?
what about the athena 60 cc kit?
Re: Make my 1 HP fly?
You don't need to kit a bike just because you put a bigger carb and exhaust on than stock. Some of the exhausts and carbs are made to deal with the higher volume flow necessitated by a kit. For example, most of the time, you would never need a 20mm carb on a stock one speed bike. That's just more air and fuel than your engine can effectively use.
Also what was mentioned before is important, if you increase the size of your carburetor, you need to increase the size of your intake as well. It doesn't do you any good to put a 15mm carb on a 12mm intake. It also doesn't do you any good to put on a bigger carb and intake if the intake port (the hole that the intake bolts to) is too small. That's where porting comes in, but porting is tricky, figure out exactly how your engine works first, then start thinking about porting.
A bigger carb and intake, as well as a performance exhaust can go a LONG way as far as making your bike go faster. Eventually you might want to change your gear ratio for more torque or top speed, or mill the head down for more low end. But a pipe and a carb+intake are a great place to start.
Do you know if your bike is a 2 speed or a one speed?
Re: Make my 1 HP fly?
It is a one speed. I am fairly sure that the stock 1 hp has the restricted intake port (9mm). I have to take the intake off to be sure, but if that is the case I might as well buy a kit or at least a stock replacement that isn't restricted. Porting really scares me at this point...
Re: Make my 1 HP fly?
dont be afraid of porting. it is very time consuming, but also very rewarding. do a search for porting, you will get some ideas on whats involved, and study study study what your doing. if you are afraid to do it to your engine, ebay one, and tinker with that
Re: Make my 1 HP fly?
you know you could also look around for a good used 2hp cylinder of even a magnum head and cylinder.
The good thing about kits is that often times people take off perfectly good cylinders and heads to put the kits on, and will let the stock stuff go for real cheap.
Re: Make my 1 HP fly?
Other than ebay, where might I look. I just missed an auction for a 2 hp...
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